Few campaigns in the modern era have been completely free of dirty politics, which generally means the use of slander, libel, forgery, or other potentially criminal acts to embarrass a political rival. Since both candidates may engage in this type of behavior during a election year, the losing candidate rarely pursues legal action after the election is over. While voters may be offended by the use of dirty politics, political campaigns are notoriously outcome-oriented, suggesting that the candidate should use any and all means necessary to guarantee a win.

One legendary but unconfirmed example of dirty politics is said to have occurred during a heated campaign between Claude Pepper and George Mathers in the 1950s. Mathers is often credited with delivering a speech describing Pepper's sister as a "well-known thespian." Pepper's brother was a "practicing homo sapiens." Pepper himself reportedly "masticated daily" or "openly matriculated at college." Although none of these allegations were in the least bit immoral or illegal, Mathers counted on voter ignorance to sway the voters away from a questionable candidate like Claude Pepper.

While that example of dirty politics may be apocryphal, there are other examples which are all too real. In 1972, an early frontrunner for the Democratic presidential race named Edmund Muskie became a victim of dirty politics. Political enemies leaked a letter to the press which allegedly contained quotes from Muskie condemning French-Canadians. This letter followed allegations of Muskie's wife being an active alcoholic. Muskie's emotional defense of his wife made him appear weak and vulnerable, two qualities not often viewed. as presidential. The "Canuck Letter" also turned out to be a complete forgery.

Dirty politics can range from invasive investigations into an opponent's personal life to complete IRS audits ordered by an incumbent president. President Richard Nixon is said to have maintained an entire staff of experts in this type of political maneuvering, including Donald Segretti and a young Republican named Karl Rove. Political enemies of the president were routinely audited for years, even television hosts such as Dick Cavett. Cavett had criticized one of Nixon's policies on-air, in front of a guest who Cavett correctly assumed worked for the Nixon White House.

Manipulative politics have played a role in American elections since the time of George Washington and Thomas Jefferson. Jefferson himself is said to have used pamphlets filled with incriminating or embarrassing information about his political opponents. Opponents of presidential candidate James Garfield in 1880 published a letter, supposedly written by Garfield himself, recommending that companies use cheap labor whenever possible, including Chinese immigrants. Garfield managed to prove the letter was a forgery before it could permanently damage his campaign.

Dirty politics can occur at any level of public service. Local political candidates often use financial records to embarrass an opponent. Family members and known political associates may also become fair game. A candidate's mental stability may be challenged, especially if he or she offers up an emotional or overheated response to political tactics. A negative ad campaign is not always the same as questionable politics, provided the charges in those ads are true and confirmable. Dirty politics often occur away from the scrutiny of the press, so many examples rarely come to light until years after the campaigns have ended.